Sequences of chemical processes that may be applied to a surface of a workpiece are limited by prior art apparatii. In one type of prior art apparatus, liquid-phase reactants are dispensed on an upper surface of the workpiece, and distribution of reactants over the surface thereof is accomplished by rotation of the workpiece at a prescribed rate. Thickness and uniformity of the film of liquid-phase reactants are determined principally by whether the liquid mixture tends to wet the workpiece surface, rotation rate, and viscosity of the liquid. In a second type of prior art apparatus, liquid-phase reactants are sprayed through one or more nozzles onto an upper or a lower surface of the workpiece. In this second type of apparatus, thickness and uniformity of the film of liquid-phase reactants are determined principally by whether the liquid mixture tends to wet the workpiece surface, the design and placement of the nozzles, rotation rate and viscosity of the liquid. It would be advantageous to provide an apparatus wherein the thickness and uniformity of liquid-phase reactant films are determined principally by features of the apparatus and wherein sequences of liquid-phase and gas-phase reactants may be applied in concert.
An apparatus for application of chemical processes to a workpiece is provided in accordance with the present invention. A first aspect of the present invention is a simple apparatus configuration that provides for movement and precise location of a workpiece within the apparatus. A second aspect of the present invention is an apparatus configuration that enables a sequence of solutions to be applied to a surface of the workpiece during processing. A third aspect of the present invention is an apparatus configuration that enables a sequence of controlled atmospheres to be provided within the apparatus chamber, thereby enabling implementation of processes that utilize liquid-phase and gas-phase reactions in concert.